The master lock excell discus combination padlocks are made with cutting edge technology to deliver unprecedented security they feature tough cut patented octagonal boron carbide shackles which are 50 tougher to cut than hardened steel they offer optimum weather resistance with the additional security of a shrouded shackle which is much tougher to pullpry open this padlock has a set your own 4 digit combination for keyless convenience supplied with a lifetime warranty against mechanical failure